1. Field of the Invention
The present invention relates to a method for implanting prosthetic implant devices and, more particularly, to a method for implantation of a femoral stem of a total hip system within the femoral canal of a femur.
2. Description of the Prior Art
The use of prosthetic implants to replace natural joints of the body, such as the hip, are well known. In hip joints, it is very often required to replace the head of the femur with a prosthetic head which requires the implantation of a prosthetic stem within the medullary canal of the femur. Heretofore the procedures for implanting a prosthetic stem include the use of a broach or rasp, usually as a last step in preparing the femoral canal for the reception of the prosthetic stem. The use of the broach or rasp as a last step is designed to provide an accurate and precise fit of the stem within the canal.
Such a broach or rasp system is shown in U.S. Pat. No. 5,089,004 dated Feb. 18, 1992 with an identical broach or rasp system shown in the 1985 Dow Corning Wright brochure entitled "The Whiteside Total Hip System".
While these instruments do provide for an accurate gauge of the shape of the broached cavity in the femur, they do not provide any means of accurately orienting the cavity itself. There has been shown a need for an instrument system which can reproduce the natural anatomy of the patient, as shown by his pre-operative x-rays, upon the implantation of a femoral component within the patient's femoral canal.
The present invention consists of a series of instruments and method for their use which accurately prepares the cavity for a precise fit with the stem and accurately orients the cavity within the medullary canal so that the patient's natural motion is duplicated upon replacement of a natural hip with a prosthetic hip. The instrument system includes a series of reamers and broaches and other instruments for locating the various bone removal operations to form a cavity precisely mimicking the stem to be implanted.